1. Field of the Invention
This invention relates to a geometric structure configuration of maglev forces in maglev rotational bearings and, in particular, to a geometric structure configuration of maglev forces with five linearly independent constraint forces, which make the rotating shaft suspended without getting into touch and friction with the static elements and whose supportive effect in axial stops is better than conventional bearings in lowering the noise and vibration as applied to the maglev rotation bearing apparatus with high-speed rotating motion.
2. Description of the Prior Art
A maglev bearing, an integration of machines, electronics, and control technology, suspends the rotating elements by the magnetic forces which suspend rotating elements and control the position of the rotating shaft It has such features as no contact, frictionlessness, no lubricant mechanism necessary and controllable system vibration, etc. According to the source of the maglev forces, there are superconducting magnets, permanent magnets and electromagnets. The maglev forces for suspending rotating elements can be either attractive or repulsive; however, since repulsive forces are not easy to control, attractive forces are commonly used as the source for suspension. According to the controlling methods of maglev forces, the maglev bearings can be classified as active, passive or hybrid types. The active maglev bearing system is a servo controlling system composed of an electro-maglev actuator, a position sensor, a controller, and a linear power amplifier. The position sensor senses the position of the sensor target on the rotating shaft, converts the size of the clearance to voltage signals and feeds it back to the servo controller. The controller then outputs controlling signals to the power amplifier, which may transform the voltage signal to a driving current to the electromagnet so as to control the position of the rotating shaft.
A conventional maglev bearing apparatus, such as R.O.C. Pat. No. 209303 (referred as the reference thereafter), mainly comprises: a maglev bearing, comprising a static element, and a rotating element, whereas one of the elements at least contains part of the other element, and one of the elements has a ring-like first magnetic element wrapping around the other element while part of which provides a second magnetic element, which usually has a circular surface and a substantial magnetic monopole in the surrounding area so that both elements keep floating on each other, and the other element further comprises a nonmagnetic cylinder sitting around the surface. The main drawbacks in its structure is that said maglev bearing apparatus utilizes permanent magnets in configuring its magnetic monopoles whose magnetic force is repulsive, which in turn means that said maglev bearing is of repulsive type. As mentioned earlier, repulsive forces are difficult to control and therefore the design of said maglev bearing is not ideal.
Moreover, other related designs of maglev bearings make use of two radial maglev suspending modules, each with two coplanar maglev constraint forces that are perpendicular to the axis and cross right at the axis, and an axial maglev suspension module, providing a constraint force along the axis. Thus, there are totally five linearly independent constraint forces in such a maglev bearing system so that rotating machines can freely rotate around the axis with frictionness. Yet other designs have suspension modules on both ends of the main axis, each with three constraint forces crossing at the end points of the main axis. However, these six constraints are linearly dependent, and only five of them are linearly independent, which can still make the 2i rotating machines freely rotating around the axis with no contact. As mentioned before, the radial maglev supporting design of the geometric configuration of said maglev forces is weak and does not take into account the application problem when the shaft suffers from larger axial load. Furthermore, the adjustment of the distance between magnetic poles and the main axis is to get the best balance against gyroscopic coupling especially in an over-hung rotor; nonetheless, the geometric configuration of current designs do not provide easy adjustment and are not ideal. Thus conventional technology has many disadvantages and needs improvement. The present invention overcomes every drawback inherent in these designs and provides a better layout of the geometry of maglev forces.